1. Field of the Invention
The present invention relates to amphibious vehicles. More specifically, the present invention relates to an amphibious vehicle having a buoyant hull with a track drive assembly, or a wheeled drive assembly, mounted on each side of the hull and hinged so that the drive assemblies can be pivoted upward and stowed on or above the deck, or pivoted downward into a driving position. When the drive assemblies are stowed in their upright position, they are positioned above the waterline and out of water flow so that the boat hull is cleaned up for optimal marine performance.
2. Description of the Related Art
Amphibious vehicles are known which are capable of providing transportation either in water or on land. Useful in areas with many bodies of water, such as lakes, rivers, swamps, and the like, an amphibious vehicle allows its operator to travel across land and, upon reaching the edge of a body of water, proceed into the water and continue on.
Many amphibious vehicles use a driving assembly, typically an assembly of wheels or caterpillar tracks that is fixed in position and cannot be retracted from the water during marine operation. The inability to remove the driving assembly from the water means that the amphibious vehicle cannot be operated at a high speed in the water because of the high drag caused by the submerged driving assembly. Maneuverability in the water is also compromised by the additional drag.
U.S. Pat. No. 3,487,802, issued on Feb. 7, 1968 to L. Roy, discloses an amphibious boat. The boat hull has a caterpillar track assembly on each side. The track assemblies can be raised and lowered vertically along each side of the hull. The track assemblies are raised during marine operation, and lowered for operation on land. During marine operation, the tracks are raised above the bottom of the hull. The tracks do not appear, however, to rise above the waterline. With the tracks still somewhat submersed in the water during marine operation, the resulting drag will prevent the amphibious boat from reaching its optimum marine performance.
U.S. Pat. No. 2,853,812, issued on Sep. 30, 1958 to A. Van Riet et al., discloses an amphibious vehicle having tractor treads alongside a shallow draft boat hull. The tractor treads can be raised and lowered vertically along each side of the hull. The tractor treads are raised during marine operation, and lowered for operation on land.
German Patent No. 647,798, published Jul. 13, 1937, discloses another amphibious vehicle that employs track drive assemblies along each side of a floating hull. Again, the tracks are vertically raised and lowered alongside the hull.
The width of the amphibious vehicle, with tracks mounted along side, presents certain limitations to use of the vehicle. One such limitation is found if the vehicle is to be trailered. Federal highway regulations limit the width of a vehicle that may be operated, or trailered, on roadways. It is desirable, for such operations, that the track assemblies of an amphibious vehicle be retractable to meet such a restriction without compromising the vehicle's aquatic performance by employing an overly narrow hull. Additionally, it may be desirable to configure the vehicle, during marine use, to a narrower width for docking and other purposes. The Roy, Van Riet, and German '798 vehicles use tracks that are raised vertically alongside the vehicle hull, thereby maintaining a constant overall vehicle width regardless of the track positions, with no capability to reduce the vehicle width.
U.S. Pat. No. 3,095,938, issued on Jul. 2, 1963 to W. Bertelsen, illustrates a ground effect vehicle having a drive track mechanism along each side of the vehicle. The vehicle can be supported and propelled by the drive tracks or, as a ground effect vehicle, by a cushion of air beneath the vehicle. The drive tracks are tilted slightly to raise the tracks' lower surface away from ground contact. This arrangement, however, leaves the vehicle with an increased width when the tracks are raised.
U.S. Pat. No. 5,181,478, issued on January 26 to S. Berardi, discloses an amphibious vehicle with a retractable drive assembly. A wheel, or caterpillar track, drive assembly is mounted on each side of the vehicle's hull. The drive assemblies can be retracted into chambers within the hull. With the drive assemblies retracted within the chambers, the chamber doors are closed. Water is pumped from the closed chambers to reduce the vehicle weight. While this approach leaves the hull cleaned up for improved marine performance, it is a relatively complex solution. The mechanically operated chamber doors must be operated in concert with the retracting wheels, and a good door seal is required to prevent water from reentering the chambers and weighting the vehicle.
U.S. Pat. No. 2,586,218, issued to A. Gazda on Feb. 19, 1952, discloses a pontoon, such as for seaplanes, sea-sleds, boat hulls, flying boats, and the like, having an endless track member retractably disposed within the pontoon. While a bevel-gear and belt mechanism is illustrated to provide drive power to the track, no power source or drive train is illustrated or disclosed. As a component of an aircraft landing gear, the track functions un-powered, with the aircraft propelled by its propeller as if on ordinary wheeled landing gear.
U.S. Pat. No. 5,400,734, issued on Mar. 28, 1995 to P. Doyon, discloses another amphibious vehicle. The Doyon amphibious vehicle employs tracks with conventional wheels that are removably mounted to the tracks. The tracks, however, are fixed. No provision is made to remove the tracks from the water, or otherwise reduce their drag, during marine operation.
Additional amphibious, and ground effect, vehicles capable of operation on both land and water are disclosed in U.S. Pat. No. 3,207,245, issued on Sep. 21, 1965 to C. Wieland, U.S. Pat. No. 3,299,849, issued on Jan. 24, 1967 to A. Pitchford, U.S. Pat. No. 3,306,250, issued on February 28 to A. Pitchford, U.S. Pat. No. 4,008,679, issued on Feb. 22, 1977 to S. Bozzano, U.S. Pat. No. 4,591,015, issued on May 27, 1986 to S. Korppoo et al., and U.S. Pat. No. 4,658,751, issued on Apr. 21, 1987 to B. Koot. U.S. Pat. Nos. 1,355,853, 1,729,374, and 5,287,938 describe additional vehicles employing a track drive assembly or arrangement for propulsion.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus an amphibious vehicle solving the aforementioned problems is desired.